Evaluation of laboratory coagulation and lytic parameters resulting from autologous whole blood transfusion during primary aortocoronary artery bypass grafting

Study Objective: To determine if autologous blood reinfusion influences overall hemostatic function following aortocoronary artery bypass graft (CABG) surgery, and if so, where the predominant area of this influence lies. Design: Prospective, with control values on each patient. Setting: Cardiac operating room of a major university-affiliated county hospital. Patients: 20 patients undergoing elective CABG surgery. Interventions: Following heparinization, and prior to cardiopulmonary bypass (CPB), venous blood (average 4.9 ml/kg) was removed via an indwelling internal jugular catheter into a preservative-free plastic transfer pack unit and stored without agitation at room temperature. This autologous whole blood was reinfused after systemic protamine reversal of heparin. Blood samples for analysis were drawn immediately before and 5 minutes after completion of the reinfusion. Measurements and Main Results: Autologous blood reinfusion appears to be significantly related to increased hemoglobin, hematocrit, platelet count, fibrinogen, plasminogen, and antiplasmin levels. The prothrombin time and activated partial thromboplastin times decreased significantly, whereas activated clotting times and D-dimer levels were unchanged. Significant increases occurred in the following thromboelastography parameters: maximum amplitude, amplitude 60 minutes after the maximum amplitude, and whole blood clot lysis index. Reaction time and coagulation time were not statistically different from control values. Conclusions: Significant improvements in coagulation and lytic parameters occur following CPB after the infusion of autologous blood. These improvements in coagulation indices may be the result of the infused blood or hemoconcentration, which is also known to occur during this period. Additional control studies are needed to differentiate these effects.